Assessment of Some Heavy Metal Concentrations in Soil and Plant at Former Converted Central Dump Site to Residential and Farming Area in Enugu State, Nigeria

This study aims to examine the levels of heavy metal contamination in the area around the former Enugu central dumpsite at Ugwuaji, which has been transformed into a residential and agricultural area. At 15-meter intervals in each of the four cardinal directions, we gathered soil and plants from the study area, while a 100-meter distance served as a control. To measure the extent of pollution, the pollution and geoaccumulation index was employed. According to the findings, the area is dirtier in the north and east than in the west and south. Of the four directions measured for soil PI, the two most abundant elements were cadmium and lead, with average concentrations of 245.28 mg/kg, 222.15 mg/kg, 239.53 mg/kg, and 218.48 mg/kg, respectively. Soil Pb PI values as follows: 28.87 mg/kg in east direction, 26.0 mg/kg in west direction, 28.01 mg/kg in north direction, and 20.92 mg/kg in south direction. While in plants the order is Pb>Cd>Cr>As>Hg, and in soil it is Cd > Pb>Hg >As > Cr, the pollution index and geoaccumulation index measure the same thing in plants. There is a great deal of contamination, as indicated by the high geoaccumulation index and pollution levels. The investigated area poses a significant risk to the environment and human health, rendering it unfit for farming or residential use unless substantial rehabilitation is carried out.